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Available in 11 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-11" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">11 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%A1%D1%96%D1%81%D1%82%D1%8D%D0%BC%D0%B0_%D0%BF%D0%B0%D0%BF%D1%8F%D1%80%D1%8D%D0%B4%D0%B6%D0%B0%D0%BD%D0%BD%D1%8F_%D0%B0%D0%B1_%D1%80%D0%B0%D0%BA%D0%B5%D1%82%D0%BD%D1%8B%D0%BC_%D0%BD%D0%B0%D0%BF%D0%B0%D0%B4%D0%B7%D0%B5" title="Сістэма папярэджання аб ракетным нападзе – Belarusian" lang="be" hreflang="be" data-title="Сістэма папярэджання аб ракетным нападзе" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Radar_v%C4%8Dasn%C3%A9_v%C3%BDstrahy" title="Radar včasné výstrahy – Czech" lang="cs" hreflang="cs" data-title="Radar včasné výstrahy" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Radar_d%27alerte_pr%C3%A9coce" title="Radar d'alerte précoce – French" lang="fr" hreflang="fr" data-title="Radar d'alerte précoce" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%A1%B0%EA%B8%B0%EA%B2%BD%EB%B3%B4%EB%A0%88%EC%9D%B4%EB%8D%94" title="조기경보레이더 – Korean" lang="ko" hreflang="ko" data-title="조기경보레이더" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Radar_peringatan_dini" title="Radar peringatan dini – Indonesian" lang="id" hreflang="id" data-title="Radar peringatan dini" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Radar_amaran_awal" title="Radar amaran awal – Malay" lang="ms" hreflang="ms" data-title="Radar amaran awal" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E6%97%A9%E6%9C%9F%E8%AD%A6%E6%88%92%E3%83%AC%E3%83%BC%E3%83%80%E3%83%BC" title="早期警戒レーダー – Japanese" lang="ja" hreflang="ja" data-title="早期警戒レーダー" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Tidligvarslingradar" title="Tidligvarslingradar – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Tidligvarslingradar" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a 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#36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 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srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Early-warning_radar" title="Special:EditPage/Early-warning radar">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Early-warning+radar%22">"Early-warning radar"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Early-warning+radar%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Early-warning+radar%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Early-warning+radar%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Early-warning+radar%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Early-warning+radar%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">April 2023</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:PAVE_PAWS_Radar_Clear_AFS_Alaska.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/9b/PAVE_PAWS_Radar_Clear_AFS_Alaska.jpg/220px-PAVE_PAWS_Radar_Clear_AFS_Alaska.jpg" decoding="async" width="220" height="193" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/9b/PAVE_PAWS_Radar_Clear_AFS_Alaska.jpg/330px-PAVE_PAWS_Radar_Clear_AFS_Alaska.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/9/9b/PAVE_PAWS_Radar_Clear_AFS_Alaska.jpg 2x" data-file-width="354" data-file-height="311" /></a><figcaption><a href="/wiki/PAVE_PAWS" title="PAVE PAWS">PAVE PAWS</a> Early-warning radar, <a href="/wiki/Alaska" title="Alaska">Alaska</a></figcaption></figure> <p>An <b>early-warning radar</b> is any <a href="/wiki/Radar" title="Radar">radar</a> system used primarily for the long-range detection of its targets, i.e., allowing defences to be alerted as <i>early</i> as possible before the intruder reaches its target, giving the <a href="/wiki/Air_defence" class="mw-redirect" title="Air defence">air defences</a> the maximum time in which to operate. This contrasts with systems used primarily for tracking or <a href="/wiki/Gun_laying_radar" class="mw-redirect" title="Gun laying radar">gun laying</a>, which tend to offer shorter ranges but offer much higher accuracy. </p><p>EW radars tend to share a number of design features that improve their performance in the role. For instance, EW radar typically operates at lower frequencies, and thus longer wavelengths, than other types. This greatly reduces their interaction with rain and snow in the air, and therefore improves their performance in the long-range role where their coverage area will often include precipitation. This also has the side-effect of lowering their <a href="/wiki/Optical_resolution" title="Optical resolution">optical resolution</a>, but this is not important in this role. Likewise, EW radars often use much lower <a href="/wiki/Pulse_repetition_frequency" class="mw-redirect" title="Pulse repetition frequency">pulse repetition frequency</a> to maximize their range, at the cost of signal strength, and offset this with long <a href="/wiki/Pulse_width" title="Pulse width">pulse widths</a>, which increases the signal at the cost of lowering range resolution. </p><p>The canonical EW radar is the British <a href="/wiki/Chain_Home" title="Chain Home">Chain Home</a> system, which entered full-time service in 1938. It used a very low pulse repetition of 25 pps and very powerful transmissions (for the era) reaching 1 MW in late-war upgrades. The German <a href="/wiki/Freya_radar" title="Freya radar">Freya</a> and US <a href="/wiki/CXAM_radar" title="CXAM radar">CXAM</a> (Navy) and <a href="/wiki/SCR-270" title="SCR-270">SCR-270</a> (Army) were similar. Post-war models moved to the <a href="/wiki/Microwave" title="Microwave">microwave</a> range in ever-increasingly powerful models that reached the 50 MW range by the 1960s. Since then, improvements in receiver electronics has greatly reduced the amount of signal needed to produce an accurate image, and in modern examples the transmitted power is much less; the <a href="/wiki/AN/FPS-117" title="AN/FPS-117">AN/FPS-117</a> offers 250 nautical miles (460 km; 290 mi) range from 25 kW. EW radars are also highly susceptible to <a href="/wiki/Radar_jamming" class="mw-redirect" title="Radar jamming">radar jamming</a> and often include advanced <a href="/wiki/Frequency_hopping" class="mw-redirect" title="Frequency hopping">frequency hopping</a> systems to reduce this problem. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Early-warning_radar&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The first early-warning radars were the British <a href="/wiki/Chain_Home" title="Chain Home">Chain Home</a>, the German <a href="/wiki/Freya_radar" title="Freya radar">Freya</a>, the US <a href="/wiki/CXAM_radar" title="CXAM radar">CXAM</a> (Navy) and <a href="/wiki/SCR-270" title="SCR-270">SCR-270</a> (Army), and the Soviet Union <a href="/w/index.php?title=RUS-2&action=edit&redlink=1" class="new" title="RUS-2 (page does not exist)">RUS-2</a><span class="noprint" style="font-size:85%; font-style: normal;"> [<a href="https://ru.wikipedia.org/wiki/%D0%A0%D0%A3%D0%A1-2" class="extiw" title="ru:РУС-2">ru</a>]</span>. By modern standards these were quite short range, typically about 100 to 150 miles (160 to 240 km). This "short" distance is a side effect of <a href="/wiki/Radio_propagation" title="Radio propagation">radio propagation</a> at the long <a href="/wiki/Wavelength" title="Wavelength">wavelengths</a> being used at the time, which were generally limited to line-of-sight. Although techniques for long-range propagation were known and widely used for <a href="/wiki/Shortwave_radio" title="Shortwave radio">shortwave radio</a>, the ability to process the complex return signal was simply not possible at the time. </p> <div class="mw-heading mw-heading3"><h3 id="Cold_War">Cold War</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Early-warning_radar&action=edit&section=2" title="Edit section: Cold War"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>To counter the threat of Soviet bombers flying over the Arctic, the U.S. and Canada developed the <a href="/wiki/Distant_Early_Warning_Line" title="Distant Early Warning Line">DEW Line</a>. Other examples (<a href="/wiki/Pinetree_Line" title="Pinetree Line">Pinetree Line</a>) have since been built with even better performance. An alternative early warning design was the <a href="/wiki/Mid-Canada_Line" title="Mid-Canada Line">Mid-Canada Line</a>, which provided "line breaking" indication across the middle of <a href="/wiki/Canada" title="Canada">Canada</a>, with no provision to identify the target's exact location or direction of travel. Starting in the 1950s, a number of <a href="/wiki/Over-the-horizon_radar" title="Over-the-horizon radar">over-the-horizon radars</a> were developed that greatly extended detection ranges, generally by bouncing the signal off the <a href="/wiki/Ionosphere" title="Ionosphere">ionosphere</a>. </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:RAF_Fylingdales_Radar.jpeg" class="mw-file-description"><img alt="RAF Fylingdales" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/64/RAF_Fylingdales_Radar.jpeg/220px-RAF_Fylingdales_Radar.jpeg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/64/RAF_Fylingdales_Radar.jpeg/330px-RAF_Fylingdales_Radar.jpeg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/64/RAF_Fylingdales_Radar.jpeg/440px-RAF_Fylingdales_Radar.jpeg 2x" data-file-width="4063" data-file-height="3054" /></a><figcaption><a href="/wiki/RAF_Fylingdales" title="RAF Fylingdales">RAF Fylingdales</a>, <a href="/wiki/Pave_Paws" class="mw-redirect" title="Pave Paws">Pave Paws</a> <a href="/wiki/Ballistic_Missile_Early_Warning_System" title="Ballistic Missile Early Warning System">Ballistic Missile Early Warning System</a>, <a href="/wiki/North_Yorkshire" title="North Yorkshire">North Yorkshire</a></figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="Modern_day">Modern day</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Early-warning_radar&action=edit&section=3" title="Edit section: Modern day"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Today the early warning role has been supplanted to a large degree by <a href="/wiki/Airborne_early_warning_and_control" title="Airborne early warning and control">airborne early warning</a> platforms.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> By placing the radar on an aircraft, the line-of-sight to the horizon is greatly extended. This allows the radar to use high-frequency signals, offering high resolution, while still offering long range. A major exception to this rule are radars intended to warn of ballistic missile attacks, like <a href="/wiki/Ballistic_Missile_Early_Warning_System" title="Ballistic Missile Early Warning System">BMEWS</a>, as the high-altitude exo-atmospheric trajectory of these weapons allows them to be seen at great ranges even from ground-based radars. </p> <div class="mw-heading mw-heading2"><h2 id="Early_systems">Early systems</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Early-warning_radar&action=edit&section=4" title="Edit section: Early systems"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Chain_Home" title="Chain Home">Chain Home</a></li> <li><a href="/wiki/Chain_Home_Low" title="Chain Home Low">Chain Home Low</a></li> <li><a href="/wiki/SCR-270" title="SCR-270">SCR-270</a></li> <li><a href="/wiki/AN/CPS-1" title="AN/CPS-1">AN/CPS-1</a></li> <li><a href="/wiki/CXAM_radar" title="CXAM radar">CXAM radar</a></li> <li><a href="/wiki/Freya_radar" title="Freya radar">Freya radar</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="1950s_through_70s">1950s through 70s</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Early-warning_radar&action=edit&section=5" title="Edit section: 1950s through 70s"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Pinetree_Line" title="Pinetree Line">Pinetree Line</a></li> <li><a href="/wiki/Mid-Canada_Line" title="Mid-Canada Line">Mid-Canada Line</a></li> <li><a href="/wiki/Distant_Early_Warning_Line" title="Distant Early Warning Line">Distant Early Warning Line</a></li> <li><a href="/wiki/Duga_radar" title="Duga radar">Duga radar</a></li> <li><a href="/wiki/Ballistic_Missile_Early_Warning_System" title="Ballistic Missile Early Warning System">BMEWS</a></li> <li><a href="/wiki/AMES_Type_80" title="AMES Type 80">AMES Type 80</a></li> <li><a href="/wiki/AMES_Type_84" title="AMES Type 84">AMES Type 84</a></li> <li><a href="/wiki/AMES_Type_85" title="AMES Type 85">AMES Type 85</a></li> <li><a href="/wiki/ROTOR" title="ROTOR">ROTOR</a></li> <li><a href="/wiki/Dnestr_radar" title="Dnestr radar">Dnestr radar</a></li> <li><a href="/wiki/Dnepr_radar" class="mw-redirect" title="Dnepr radar">Dnepr radar</a></li> <li><a href="/wiki/Daryal_radar" title="Daryal radar">Daryal radar</a></li> <li><a href="/wiki/Linesman/Mediator" title="Linesman/Mediator">Linesman/Mediator</a></li></ul> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:E-3aawa.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/23/E-3aawa.jpg/200px-E-3aawa.jpg" decoding="async" width="200" height="145" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/23/E-3aawa.jpg/300px-E-3aawa.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/23/E-3aawa.jpg/400px-E-3aawa.jpg 2x" data-file-width="560" data-file-height="407" /></a><figcaption>AWACS plane</figcaption></figure> <div class="mw-heading mw-heading2"><h2 id="Operational_systems">Operational systems</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Early-warning_radar&action=edit&section=6" title="Edit section: Operational systems"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Airborne_early_warning_and_control" title="Airborne early warning and control">AWACS</a>, the US airborne system of surveillance radar plus command and control functions</li> <li><a href="/wiki/Daryal_radar" title="Daryal radar">Daryal radar</a>, Soviet and Russian early warning radar</li> <li><a href="/wiki/Dnestr_radar" title="Dnestr radar">Dnestr radar</a>, Soviet and Russian early warning radars</li> <li><a href="/wiki/Don-2N_radar" title="Don-2N radar">Don-2N radar</a>, Russian missile defence radar in Moscow</li> <li><a href="/wiki/Duga_radar" title="Duga radar">Duga radar</a>, Soviet over-the-horizon early-warning radar system</li> <li><a href="/wiki/Dunay_radar" title="Dunay radar">Dunay radar</a>, Soviet missile defence radar</li> <li><a href="/wiki/GIRAFFE_Radar" class="mw-redirect" title="GIRAFFE Radar">GIRAFFE</a>, Swedish family of early warning radar systems</li> <li><a href="/wiki/EL/M-2080_Green_Pine" title="EL/M-2080 Green Pine">EL/M-2080 Green Pine</a>, Israeli ground-based missile-defense radar by Elta</li> <li><a href="/wiki/EL/M-2090" title="EL/M-2090">EL/M-2090</a>, Israeli ground-based very long range early-warning radar system</li> <li><a href="/wiki/Erieye" title="Erieye">Erieye</a>, Swedish airborne system of surveillance radar</li> <li><a href="/wiki/Jindalee_Operational_Radar_Network" title="Jindalee Operational Radar Network">Jindalee</a>, Australian over-the-horizon radar network</li> <li><a href="/wiki/Long_Range_Discrimination_Radar" title="Long Range Discrimination Radar">Long Range Discrimination Radar</a>, the US radar system</li> <li><a href="/wiki/North_Warning_System" title="North Warning System">North Warning System</a>, a joint United States and Canadian early-warning radar system</li> <li><a href="/wiki/DRDO_AEW%26CS" title="DRDO AEW&CS">NETRA</a>, Indian airborne early warning and control aircraft</li> <li><a href="/wiki/PAVE_PAWS" title="PAVE PAWS">PAVE PAWS</a>, the US early warning radar</li> <li><a href="/wiki/RAF_Fylingdales" title="RAF Fylingdales">RAF Fylingdales</a>, British early warning radar</li> <li><a href="/wiki/Red_Color" title="Red Color">Red Color</a>, Israeli early warning radar system</li> <li><a href="/wiki/Sea-based_X-band_Radar" class="mw-redirect" title="Sea-based X-band Radar">Sea-based X-band Radar</a>, the US sea-based early-warning radar station</li> <li><a href="/wiki/Voronezh_radar" title="Voronezh radar">Voronezh radar</a>, Russian early warning radar system</li> <li><a href="/wiki/ESR-32A" title="ESR-32A">ESR-32A</a>, Egyptian air surveillance and early-warning radar system</li> <li><a href="/w/index.php?title=ASELSAN_ALP-300G&action=edit&redlink=1" class="new" title="ASELSAN ALP-300G (page does not exist)">ASELSAN ALP-300G</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Early-warning_radar&action=edit&section=7" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFWragg1973" class="citation book cs1">Wragg, David W. (1973). <i>A Dictionary of Aviation</i> (first ed.). Osprey. p. 13. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/9780850451634" title="Special:BookSources/9780850451634"><bdi>9780850451634</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=A+Dictionary+of+Aviation&rft.pages=13&rft.edition=first&rft.pub=Osprey&rft.date=1973&rft.isbn=9780850451634&rft.aulast=Wragg&rft.aufirst=David+W.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEarly-warning+radar" class="Z3988"></span></span> </li> </ol></div></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Early-warning_radar&oldid=1267559490">https://en.wikipedia.org/w/index.php?title=Early-warning_radar&oldid=1267559490</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Radar" title="Category:Radar">Radar</a></li><li><a href="/wiki/Category:Early_warning_systems" title="Category:Early warning systems">Early warning systems</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_matches_Wikidata" title="Category:Short description matches Wikidata">Short description matches Wikidata</a></li><li><a href="/wiki/Category:Articles_needing_additional_references_from_April_2023" title="Category:Articles needing additional references from April 2023">Articles needing additional references from April 2023</a></li><li><a href="/wiki/Category:All_articles_needing_additional_references" title="Category:All articles needing additional references">All articles needing additional references</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 5 January 2025, at 17:49<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. 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